Article: Bajocian Sonniniidae and other ammonites from western Scotland

The sequence of Bajocian ammonites in the Bearreraig Sandstone of Skye is summarized in terms of a modified scheme of zones or subzones: Discites, Ovalis, Laeviuscula, Sauzei (with subzone Sauzei and a new upper subzone Hebridica), and Humphriesianum (with subzones Cycloides, Humphtiesianum, and Blagdeni). The first three are used informally to replace Sowerbyi, but Sauzei and Humphriesianum, with subzones as above, can be regarded as part of a formal Lower Bajocian zonal scheme. Upper Bajocian zones cannot yet be distinguished in Skye. Part of the family Sonniniidae is modified and discussed, and the species of Euhoploceras (with subgenera Euhoploceras and Fissilobiceras), Shirbuirnia, Witchellia, Pelekodites, Sonninia (with subgenera Sonninia and Papil-liceras), and Dorsetensia which are present in western Scotland are described, together with some other ammonites. There is clear dimorphism in some of the faunas, for example Witchellia (M) and Pelekodites (m), but Pelekodites (m) also occurs with Sonninia (M+?m), and pairing of dimorphs is obscure and so not attempted. Some species in Scotland are slightly dwarfed in comparison with other parts of Europe.